Telephonic and radiotelephonic message or audition by means of fluid resistance

Title:

Telephonic and radiotelephonic message or audition by means of fluid resistance

United States Patent 1568046

Inventors:

Ernest, Bertron

Publication Date:

01/05/1926

Export Citation:

Assignee:

Ernest, Bertron

Primary Class:

381/77

International Classes:

H04B1/16; H04M1/00; H04B1/16; H04M1/00

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